(* Title: Pure/context_position.ML
Author: Makarius
Context position visibility flag.
*)
signature CONTEXT_POSITION =
sig
val is_visible: Proof.context -> bool
val set_visible: bool -> Proof.context -> Proof.context
val restore_visible: Proof.context -> Proof.context -> Proof.context
val if_visible: Proof.context -> ('a -> unit) -> 'a -> unit
val reported_text: Proof.context -> Position.T -> Markup.T -> string -> string
val report_text: Proof.context -> Position.T -> Markup.T -> string -> unit
val report: Proof.context -> Position.T -> Markup.T -> unit
end;
structure Context_Position: CONTEXT_POSITION =
struct
structure Data = Proof_Data
(
type T = bool;
fun init _ = true;
);
val is_visible = Data.get;
val set_visible = Data.put;
val restore_visible = set_visible o is_visible;
fun if_visible ctxt f x = if is_visible ctxt then f x else ();
fun reported_text ctxt pos markup txt =
if is_visible ctxt then Position.reported_text pos markup txt else "";
fun report_text ctxt pos markup txt = Output.report (reported_text ctxt pos markup txt);
fun report ctxt pos markup = report_text ctxt pos markup "";
end;